Talks aimed at averting national rail strikes this summer have been adjourned until next week.
RMT union threatening first national rail strike in a decade
Leaders of the Rail Maritime and Transport (RMT) union met Network Rail officials to hold preliminary discussions on Friday.
The union is seeking to increase the 3% pay offer and obtain travel concessions for Network Rail (NR) staff.
The talks were described as "very constructive and amicable" by a spokesman for NR.
The RMT says 58% of its members voted in favour of walkouts.
But according to NR, which hopes to settle the dispute, strike proposals were backed more heavily by maintenance staff than by signal workers.
Union members are also protesting at the closure of the company's final salary pension scheme to new workers.
If strikes do go ahead, they are expected to cause the worst disruption on the railways for 10 years.
NR chief executive John Armitt recently told BBC News the RMT's demands on pension and travel would cost £40m and the pay demand £11m.
The extra money was more than the cost of an original 3% pay offer, according to Mr Armitt, who added: "There is not a lot of money available."